Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 83 insertions, 0 deletions

diff --git a/kernel/Documentation/x86/x86_64/machinecheck b/kernel/Documentation/x86/x86_64/machinecheck
new file mode 100644
index 000000000..b1fb30273
--- /dev/null
+++ b/kernel/Documentation/x86/x86_64/machinecheck
@@ -0,0 +1,83 @@
+
+Configurable sysfs parameters for the x86-64 machine check code.
+
+Machine checks report internal hardware error conditions detected
+by the CPU. Uncorrected errors typically cause a machine check
+(often with panic), corrected ones cause a machine check log entry.
+
+Machine checks are organized in banks (normally associated with
+a hardware subsystem) and subevents in a bank. The exact meaning
+of the banks and subevent is CPU specific.
+
+mcelog knows how to decode them.
+
+When you see the "Machine check errors logged" message in the system
+log then mcelog should run to collect and decode machine check entries
+from /dev/mcelog. Normally mcelog should be run regularly from a cronjob.
+
+Each CPU has a directory in /sys/devices/system/machinecheck/machinecheckN
+(N = CPU number)
+
+The directory contains some configurable entries:
+
+Entries:
+
+bankNctl
+(N bank number)
+	64bit Hex bitmask enabling/disabling specific subevents for bank N
+	When a bit in the bitmask is zero then the respective
+	subevent will not be reported.
+	By default all events are enabled.
+	Note that BIOS maintain another mask to disable specific events
+	per bank.  This is not visible here
+
+The following entries appear for each CPU, but they are truly shared
+between all CPUs.
+
+check_interval
+	How often to poll for corrected machine check errors, in seconds
+	(Note output is hexademical). Default 5 minutes.  When the poller
+	finds MCEs it triggers an exponential speedup (poll more often) on
+	the polling interval.  When the poller stops finding MCEs, it
+	triggers an exponential backoff (poll less often) on the polling
+	interval. The check_interval variable is both the initial and
+	maximum polling interval. 0 means no polling for corrected machine
+	check errors (but some corrected errors might be still reported
+	in other ways)
+
+tolerant
+	Tolerance level. When a machine check exception occurs for a non
+	corrected machine check the kernel can take different actions.
+	Since machine check exceptions can happen any time it is sometimes
+	risky for the kernel to kill a process because it defies
+	normal kernel locking rules. The tolerance level configures
+	how hard the kernel tries to recover even at some risk of
+	deadlock.  Higher tolerant values trade potentially better uptime
+	with the risk of a crash or even corruption (for tolerant >= 3).
+
+	0: always panic on uncorrected errors, log corrected errors
+	1: panic or SIGBUS on uncorrected errors, log corrected errors
+	2: SIGBUS or log uncorrected errors, log corrected errors
+	3: never panic or SIGBUS, log all errors (for testing only)
+
+	Default: 1
+
+	Note this only makes a difference if the CPU allows recovery
+	from a machine check exception. Current x86 CPUs generally do not.
+
+trigger
+	Program to run when a machine check event is detected.
+	This is an alternative to running mcelog regularly from cron
+	and allows to detect events faster.
+monarch_timeout
+	How long to wait for the other CPUs to machine check too on a
+	exception. 0 to disable waiting for other CPUs.
+	Unit: us
+
+TBD document entries for AMD threshold interrupt configuration
+
+For more details about the x86 machine check architecture
+see the Intel and AMD architecture manuals from their developer websites.
+
+For more details about the architecture see
+see http://one.firstfloor.org/~andi/mce.pdf